There may be no single cause of bipolar disorder (aka manic depression). Instead, research indicates the causes of bipolar disorder are probably a combination of biochemical, genetic and environmental factors that may trigger and perpetuate the chemical imbalances in the brain.
Net worth: $829 million. Telecommunications mogul Strive Masiyiwa is widely regarded as the richest man in Zimbabwe and is one of the richest men in Africa with a net worth of more than US$800 million.
Hereâs the full list of the â26 richest people of all timeâ: 1  1. Mansa Musa I, (Ruler of Malian Empire, 1280-1331) $400 billion. 2  2. Rothschild Family (banking dynasty, 1740- ) $350 billion. 3  3. John D Rockefeller (industrialist, 1839-1937) $340 billion. 4  4. Andrew Carnegie (industrialist, 1835-1919) $310 billion.